Process of separating iron pyrites from zinc-blende.



Patented March 5, 1 904.

. UNITED STATES, PATENT OFFICE.

KARL DANZIGER, OF ZAWODZE, NEAR KA'ITOWITZ, GERMANY.

PROCESS OF SEPARATING IRON PYRITE S FROM ZlNC-BLENDE.

SPECIFICATION formingpart of Letters Patent No. 754,643, dated March 15,1904. Application filed May 29, 1903. Serial No. 159,324. (Nospecimens.)

To all whom/it may concern.-

Be it known that I, KARL DANZIGER, of

Zawodze, near Kattowitz, Upper Silesia, in the German Empire, haveinvented a new and useful Process of Separating Iron Pyrites fromZinc-Blende, of which the following is aspecification.

I have found that if the zinc-blende, preferably in a ground state, isspread on a floor heated by fire-gases or the like the iron pyriteswhich is contained in the zinc-blende is transferred by oxidation underthe influence of heat and moisture into ferric salts, (sulfate of iron,)which are soluble in water, while the zinc sulfid is not affected by theoxidizing action.

The process may be illustrated by the following formula:

The sulfuric acid formed by the oxidizing process acts on the otherelements of the ore and forms sulfates of alumina, of magnesia,

of lime, and other sulfates. This action of the sulfuric acid is veryuseful for the process, as it decomposes the ore. After the oxidation ofthe sulfid of iron or pyrite is finished the ferrous salt is extractedby water and the remaining zinc ore is dried, which may be done on thesame floor.

In carrying out my invention I preferably use a floor under which arearranged channels. Through these channels I lead the (waste) fire-gasesfrom the steam-boilers or from kilns to the chimney. In this manner thecaloric content of these gases, which is generally lost, is usedprofitably. On the floor the zincblende is spread and may be exposedalso to the action of air and moisture, which under the action of theheat decompose and oxidize the pyrite component of the ore.

Having now described my invention, What I claim, and desire to secure byLetters Patent, is

A process for separating iron pyrite from zinc-blende, which consists inexposing the zinc-blende to the action of air moisture and heat andextracting the ferrous salt, which has been formed by the oxidizingaction by water.

In witness whereof I have hereunto set my hand in presence of twowitnesses.

KARL DANZIGER.

Witnesses:

HENRY HARPER, WOLDEMAR HAUPT.

